Method of drying or treating timber and the like



April 29, 1930. F. w. CHERRINGTON 1,756,281

METHOD OF DRYING OR TREATING TIMBER AND THE LIKE Original Filed Dec. 17, 1925 iii Z )1 MIQIIP 9a f Q {Kg/m" W 7/1 55225 RF'EEEE'ZE //7 @421 i if :1 I if ff Ems u glm'wtv INVENTE:

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Patented pr. 29, 1936 ENTE ore-ma.

. FRANK W. GHERRIKGTON, OI! TOLEDO, OHIO METHOD OF DRYING OR TREATING TIMBER AND THE continuation of application Serial No. 681,295, filed December 17, 1923. This application filed June 14,

1838. Serial No. 285,466.

This invention relates to a method of ,dry-

mg or treating timber or similar material having cells or ducts which are arranged in.

more or less parallel relation and, in a piece of timber, correspond to the grain of the wood which extends from one end thereof to the other.

The present application is a continuation of my earlier application filed December 17,

1923, Serial No. 681,295.

'It is a fact that, prior to my invention, no method had been known by means of which wood or timber could be economically and speedily dried. N atures own method of drying, employing the elements of time and an, is still in extensive use. Kiln dried lumber constitutes only a small proportion of the total amount of lumber used and is limited to a-thickness of not more than four inches.

It takes several weeks for proper kiln drying,

. while the present method takes only a few hours. Air dried lumberv is stronger, more durable and more economical for use in scores of important industries, among which may be mentioned the railroads and the manufacturers of automobiles and various implements. e

In natures method of air seasoning, considered .to be the best, the green timbers are so stacked in such a manner as to allow free circulation of air on all sides. The air, which is drier than the green timbers, absorbs moisture from the. surface fibres of the wood. As

the surface dries, capillarity draws'moisture V and this flow ofmoisture is mainly toward the ends of the timber. The moisture contentin green timber is about most of which is free sap and water contained in the wood cells orducts. This free sap and water naturally are the first tobe expelled by capil ,larity and then comes the slower expulsion of the water and sap actually within the wood cells. 7 As these wood cells lose their moi sture, they dry and harden, and this'gives the seasoned wood its strength. The obj ectof my invention is to provide a method of drying which follows natures method as close- 1y as possible, except as to the time required, which is reducedto a mimmum. It is easily fromthe interior of the wood to the surface demonstrated that, if the wood is rotated, with its cellular structure or sa ducts parallel to the resultant centrifuga force, that is, radial to the axis of rotation, the capillary action forcing the water and sap to the surface will be accelerated in proportion to the speed of rotation and the distance from the axis of rotation. If dry air is admitted through the top of a closed container, within which green timbers are rotated in this manner, it will become saturated with moisture expelled from the ends, and will gravitate toward the bottom of the container, where it may be withdrawn.

It is upon these physical princi les that my invention is based. Thus a spee ,harmless, and econominal means of extracting the moisture from green timbers is provided. In order that my invention may be fully understood, I have illustrated, in the accompanying drawings, apparatus by means of which'the method may be carried out. In the drawings Figure 1 is a side elevation of one type of apparatus.

Fig. 2 is a plan View of another type of apparatus, including a container which isshown in section.

Fig. 3 is a detail view of a timber or tie holder, which may be used in connection with the apparatus.

Fig. 4 is an end elevation of a tie in a holder- According to Figure 1, the apparatus is driven by a motor 1 having a shaft 2 which carries a bevel pinion 3 in mesh with a bevel gear 4.- secured to the upper end of a vertical shaft 5. The motor 1 is mounted on a platform :6, on which is a counterbalanee'l. The apparatus is supported by bearings 8 in a member 9, which in turn is sup orted by bearings 10 in a fixed overhead rame 11, supported by uprights 12-forming a, base 13. The

shaft 5, thus suspended, may be rotated/at ahigh speed. A series of spiders are secured,

to theshaft 5, and secured to each spider are a series of radially extending pockets 14. each adapted to receive a railroad tie 15, or other piece of timber for which the a paratusis adapted. Each pocket 14 may suitably construc e to lamp or otherwise retain the timber 15, and a bolt 16, or other means engaging the outer end of the timber prevents the latter from being thrown outwardly by the centrifugal force developed by the rapid rotation of the same about its axis.

In the form shown in Fig. 2, the motor 17 has a shaft 18 connected by a suitable coupling 19 to a main drive shaft 20, on which gears 21 are-mounted. These gears may be selectively connected to the shaft 20 by clutches 22, which are controlled from an operators station by levers 23. .Each gear 21 is in mesh with a gear 24 secured to a shaft section 25 mounted in bearings 26. The shaft sections 25 are in alinement with each other and each carries a series of pockets 14 like those secured to the shaft 5 in Fig. 1. The rotating frame may be enclosed in a chamber 27, which may be provided with doors 28 for inserting or removing the timber. Dry air, steam or impregnating liquid may be supplied to the chamber through a pipe 29, controlled by a valve 30. The impregnating liquid may be drawn off or the chamber exhausted through a pipe 31, controlled by a valve 32.

In drying and treating railroad ties according to my improved method, the rotatable frame is loaded with green ties, which are securely anchored in the pockets 14 so that they may be rotated at a speed as high as fifteen hundred revolutions per minute. The

rotating frame is preferably arranged to rotate about the vertical axis, and sinceconsiderable air circulation is generated by the rotation, there is less resistance and consequently less consumption of power, if the rotating frame is enclosed within a chamber.

All of the pockets 14 extend radially from the axis of rotation, their inner ends being far enough from the axis to accommodate the desired number. As the timbers are thus held and rotated, the centrifugal force developed will act continuously in one direction len hwise of each duct, from one end thereof to t e other and the rotation is rapid enough to cause a continuous flow of moisture from the outer ends of the timbers until they are thoroughly dried. Y

After the ties have been rotated until they are thoroughly air dried, any known process of treatingthem with creosote oil or the like,

may be used without removing the ties from the chamber. When the ties have been thoroughly/treatedwith creosote oil, they may .be again rotated until all surplus creosote is removed, so that there is a maximum pene tration of preservative with a minimum quan- Surplus creosote thus may, of course, f t e chamber,-

My method of seasoning and treating timber has many advantages over the natural method which is most commonly used. It eliminates acres of storage yards, tracks and millions of ties for many months while they are being seasoned, and thus releases millions of dollars of capital, with consequent saving in interest, depreciation, insurance and handling. It eliminates a great deal of expensive equipment now employed in treating timber. An absolute minimum of oil is used to secure maximum penetration. The ties, after being treated, are quite dry and easily handled.

It should also be noted that, in the natural drying of timber, the sap and moisture are conveyed to the surface of the timber only by capillary action. This process is necessarily slow, with the result that the cell or duct walls dry more rapidly at the surface than in the interior of the timber, causing shrinkage or collapse of the cell walls and consequent checking or. cracking at the ends. In the treatment of the timber according to my method, the moisture which is discharged from the ends of the timber is rapidly replaced by moisture which is forced outwardly from the interior of the timber. This flow takes place at such. speed that there is substantially no drying or hardening of the duct Walls at the. end of the timber. A rapid and uniform seasoning of the timber throughout its entirelength is thus effected and there is substantially no checking or cracking. This makes it unnecessary to use 3 or Z irons at the ends of the timber, as are necessary with timber dried by other methods.

While I have illustrated apparatus which may be used in carrying out my method, it is, of course, to be understood that this is only for the purpose of illustration and is not to be regarded as in any way limiting the scope of the invention as claimed.

What I claim is:

1. The hereindescribed method of treating or drying timbers or other like materials,

which resides in rotating the material so as to cause progressive movement of the duct contents thereof from one end to the o posite end ofthe ducts and outwardly o the axis of rotation.

2. The hereindescribed method of treating or drying timbers or other like materials, which resides in rotating the material with the latter disposed radially of the axis of rotation so as to cause progressive movement of the duct contents thereof by centrifugal ac- 5 equipment. It makes it unnecessary to store tion from the inner to the outer end of the ducts and outwardly bf the axis. of rotation.

3. The hereindescribed method of treating or drying timbers or the like which resides in subjecting the duct contents to cenducts to finally expel the contents through the latter of said ends of the ducts.

4. The hereindescribed method of treating or drying timbers or the like which resides in subjecting the duct contents in the presence of a heated drying fluid or drier to centrifugal force directed in such a manner as to cause progressive movement of the duct contents from one to the other end of the ducts to finally expel the contents through the latter of said ends of the ducts.

5. The hereindescribed method of treating I or drying timbers or the like which resides in subjecting the duct contents to centrifugal force actmg'along the length of the ducts from one end to the other.

6. The method of treating or drying material having ducts therein, which consists in rotating the material about an axis while said material is held in such a position with respect to said axis that centrifugal force acts lengthwise of each duct from one end to the other.

7. The method of treating or drying material having ducts therein, which-consists in so arranging and holding the material with reference to an axis that each duct, substan-. tially from'one end of said duct to the other, extends away from the axis, and rotating the material, vwhile it is so held, about said axis.

8. The method of treating timber which consists in arranging and holding several pieces in such a position that the sap ducts are in substantially radial relation to a common axis, and rotating the same, while so held, about said axis, whereby the centrifugal force thus developed tends to drive the contents of each duct continuously from one end of the duct to the other.

In testimony whereof, I have hereunto signed my name to this specification.

FRANK w GI-ERBINGTQN. 

